Energy Mechanism of Rock Burst in the Rock-Coal Combined Body

Rock burst hazards during deep mining are a dynamic phenomenon of the sudden release of elastic energy aggregated in the roof rock-coal combined body. In this paper, the occurrence mechanism of rock burst for roof rock-coal combined body was studied through energy dissipation theory. And the elastic energy attenuation degree of combined body was defined. Additionally, the effects of height ratio of roof rock to coal and elastic modulus of roof rock or coal on the rock burst were analyzed in the potentiality of the combined body. Results show that the elastic energy attenuation degree is positively correlated with the equivalent elastic modulus of combined body. And the equivalent elastic modulus is shown to a positive correlation with the height ratio of roof rock to coal and elastic modulus of roof rock or coal. Generally, the larger the height ratio and elastic modulus of roof rock or coal are, the great the equivalent elastic modulus is and the stronger the elastic energy attenuation degree is. And the roof rock-coal combined body easily occurs in rock burst. The above achievements are of great significance to understand the elastic energy attenuation characteristics and to prevent rock burst hazards of the roof rock-coal combined body.